The effect of the downturn in oil prices on the external surpluses of the GCC countries

The paper examines the impact of the downturn in oil prices on the performance of the external sectors of the members of the Gulf Co-operation Council (GCC). The paper also developes and tests a simultaneous-equations model to examine the interaction between the economies of the GCC and the rest of the world. The analysis shows that the slump in oil exports has reduced drastically the external surplus of the GCC and has resulted in structural shifts in the import and resource balance functions.     

Reaction of hydroxymethylanthraquinones with thionyl chloride

The reaction of thionyl chloride with some hydroxymethylanthraquinone derivatives was investigated. The reaction product was found to be dependent on other ring substituents and on the reaction temperature. In the case of amino derivatives and at lower temperatures, chlorosulphinylmethylanthraquinones were obtained; while at higher temperatures, chlorination of the anthraquinone nucleus occurred. Hydroxy derivatives gave only chloromethyl compounds.     

The Conversion of 2,4-Dinitrophenylhydrazine derivatives of monocarbonyls to ethylenethioacetals and ethylenethioketals for analysis by gas liquid chromatography

A method was developed for the direct conversion of 2,4-dinitrophenylhydrazones (2,4-DNPHS) ofn-al-kanals and methylketones int ethylenethioacetals and ethylenethioketals for analysis by gas liquid chromatography (GLC). the method depended on heating the 2,4-DNPHS and 1,2-ethanedithiol with boron fluoride (BF₃) ethyl ether at 125 C for 12 min or withp-toluenesulfonic acid at 200 C for 15 min. The reaction was extracted with pentane, and after evaporation, the product was dissolved ono-cylene and injected into the GLC. High yields of above 90% were obtained from long chain 2,4-DNPHS and somewhat lower yields of about 80% were obtained from short chain 2,4-DNPHS. Eight standard ethylenethioacetals and ethylenethioketals were synthesized; their elemental analysis, bp, mp, and retention times on FFAP and SE-30 GLC columns were determined.     

A facile synthesis and tautomeric structure of novel 4‐arylhydrazono‐3‐(2‐hydroxyphenyl)‐2‐pyrazolin‐5‐ones and their application as disperse dyes

The main target of this paper was the synthesis of novel azo disperse dyes with better dyeing properties, together with a systematic investigation to determine their dominant tautomer(s) from 12 possible tautomeric structures. In this regard, novel azopyrazolin‐5‐one dyes were synthesised via the reaction of hydrazine hydrate with 2,3,4‐chromantrione‐3‐arylhydrazones. The acid dissociation constants both in the ground and in the excited state for the series prepared were determined and correlated by the Hammett equation. The results of this correlation, together with spectral data, indicated that the compounds under scrutiny exist predominantly in the keto‐hydrazo structure as a Z‐configuration, both in the ground and in the excited state. Finally, the synthesised dyes were applied as disperse dyes for dyeing polyester fabrics, and their fastness properties were evaluated. Also, the position of colour in CIELAB coordinates was estimated and discussed.     

A study on Claisen Condensation with Diethyl Anilinodiacetate

Sodium hydride prompted reactions of diethyl anilinodiacetate 1 with acetophenone, p-nitroacetophenone, p-fluoroacetophenone and acetylthiophene result in the formation of tetraketones 3a–d . Evidence is presented to support the formation of 3a–d , via a sequence of reactions involving condensation with hydrazine, their acetyl derivatives, and cyclization with polyphosphoric acid. The structures of the hitherto unknown ring systems have been confirmed by i.r., p.m.r. and mass spectral data.     

Thermal and magnetic analyses of gas-insulated lines

This paper presents the factors affecting current rating “ampacity” of buried three-phase, naturally cooled isolated-phase gas-insulated lines (GIL) with flat formation and finite-element simulation of double-circuit, three-phase GIL inside a tunnel to calculate the magnetic-flux and current densities. In the former analysis, the depth of GIL burial, interspacing of phases and soil thermal resistivity are investigated to show their impacts on the GIL ampacity. In the latter analysis, the effects of electrical and physical arrangements of GIL phases on the magnetic-flux density inside and outside the tunnel, and the current density in few installed liquefied natural gas (LNG) pipelines, which run in parallel to the GIL inside the tunnel, are also studied. In any GIL configuration, the magnetic field impact is always extremely low. Localized hot spots along the periphery of the GIL enclosure are found and corrosion can be accelerated due to temperature gradient. Moreover, there is a possibility of galvanic corrosion of the enclosures when they are bonded together and with the gallery steel reinforcement at very short length intervals. The simulation results also give the best location of the LNG pipelines or any cables to have the lowest electromagnetic induction. The configuration that has the best “magnetic behavior” is distant-placed arrangement (DPA) with (abc–cba) phase arrangement. The induced eddy-current density in the LNG pipelines is very low and hence its thermal effects can be neglected.     

Design of a microprocessor-controlled PABX

A complete design of a small ‘private automatic branch exchange’ (PABX) system serving 32 subscribers is introduced, using the simplest and most direct design procedures. The system uses space division analogue switching concepts and allows four internal and two external calls at the same time. A logical design is first carried out to give the evolution of the state of a subscriber during call processing, followed by a complete design of the microprocessor circuits. All external circuits responsible for counting and storing dialled digits, generating telephone tones and interfacing are described. All programs and subroutines are discussed and several flowcharts are given to describe the controlling program. Finally the advantages, disadvantages and the system limitations are discussed. The design uses an Intel 8080 microprocessor with 2 kbyte of EPROM and 256 byte of RAM.     

Study of the efficacy of the new antischistosomal drug 10-[2-(diethylamino)ethyl]-9-acridanone-(thiazolidin-2-ylidene) hydrazone against an Egyptian strain of S. mansoni in mice

The efficacy of 3 doses (10, 15 and 20 mg/kg) of the new antischistosomal drug Ro 15-5458 (10-[2-(diethylamino)ethyl]-9-acridanone-(thiazolidin-2-ylidene)hy drazone, CAS 092928-47-7) against an Egyptian strain of S. mansoni was studied in mice. The effect of duration of infection on the response of mice to treatment with 20 mg/kg was evaluated at 7 and 12 weeks after infection. The criteria used for the assessment of drug efficacy were: worn count and distribution in the liver and portomesenteric system, oogram changes in the small intestine, estimation of the number of ova/g stood, liver and intestine and histopathological examination of mice liver. Data revealed a dose dependent decrease in number of adult worms and number of ova/g stool, liver and intestine. A reduction of 83.6, 89.4 and 94.9% in mean number of schistosomes compared to control was recorded following treatment with 10, 15 and 20 mg/ kg of the drug, respectively. Oogram changes were more remarkable following treatment with 20 mg/kg as evidenced by complete disappearance of all immature stages. Treatment with Ro 15-5458 in a dose of 20 mg/kg resulted in complete disappearance of couples and 100% shift or worms to the live. Examination of mice liver 2 weeks post treatment revealed on changes in pathology following treatment with 10 mg/kg compared to control. Treatment with 20 mg/kg gave better results comparable to 15 mg/kg, a decreased number and size of granulomas with minimal areas of necrosis was observed. Parasitological cure was effectively achieved when treatment was initiated 7 or 12 weeks post infection. However, histopathological data revealed that the earlier the treatment the better the results.     

Synthesis and antibacterial testing of some new quinolines, pyridazinoquinolines and spiroindoloquinolines

Spinal hydatid cyst was diagnosed in four patients, aged between 21 and 35 years, three male and one female between 1983 and 1993. In three patients, the cysts were epidural and in one intra-vertebral. All patients presented with symptoms of spinal cord compression. Surgical treatment was performed in all of the patients. One patient who relapsed showed evidence of cure after a second operation, and was given mebendazole (Vermox). Histological examination was performed in all of the patients.     

Corrugated steel webs for prestressed concrete girders

In the past two decades, there has been increasing interest in prestressed girders with corrugated steel webs in bridge construction. The objective of a recent study at the University of Calgary is two-fold. The first is to review and refine the theoretical background for the shear strength of corrugated steel webs. The second is to experimentally investigate the shear and flexural behaviour of composite prestressed I-girders made with such webs. The analytical study shows that the geometry of corrugated steel webs can be chosen to provide the highest shear strength for the least volume of steel with negligible sensitivity to small variations in the corrugation angle. Contrary to published data, the existence of an additional post buckling shear strength as high as 82% of the total shear strength was experimentally confirmed. The experimental results confirm that while the shear is supported by the corrugated steel web, flexure is almost entirely supported by the prestressing steel and reinforcing bars in the bottom flange in tension, and the concrete top flange in compression.